Re: [PATCH] Add TAINT_DRIVER_OVERRIDE for usage of driver_override

["Uwe Kleine-König" <u.kleine-koenig@baylibre.com>]

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Hello David,

On Fri, Sep 25, 2026 at 08:20:40PM +0200, Uwe Kleine-König wrote:
> Commit fcbfaffee51a ("driver core: add TAINT_FORCED_BIND for when
> userspace manually messes with devices and drivers") introduced a taint
> for usage of bind/unbind sysfs files that manually trigger driver probe
> and remove respectively.
> 
> For drivers that do their resource management correctly (which is also
> needed for module unloading) bind and unbind for matching devices are
> not critical operations. The thing that makes bind and unbind unsafe is
> that drivers can be forced on devices that originally don't match using
> driver_override. The result is that e.g. of_device_get_match_data()
> returns NULL despite all .of_match_table entries having a non-NULL
> .driver_data member which yields a NULL pointer exception for several
> drivers. And given that after setting a driver_override a manual bind is
> only one way a driver can be bound to an unexpected device, a separate
> taint for such an override is justified.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

Sashiko found an issue in the oneline shell script, I fixed that in a
separate commit because it wasn't introduced in my patch.

Also I violated my own rule not to send patches directly before calling
it a day and so missed to squash in the build fix that Sashiko also
found 🤦.

I wait a bit before sending a v2, but if you want to take a glimpse
already on the changes I did, look at

	https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux.git driver_override-taint

Best regards
Uwe

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